fix: upgrade postcss from 8.4.25 to 8.4.26

Snyk has created this PR to upgrade postcss from 8.4.25 to 8.4.26.

See this package in npm:
https://www.npmjs.com/package/postcss

See this project in Snyk:
https://app.snyk.io/org/data.gov/project/22700983-7a0f-49aa-b664-c3f0abc51588?utm_source=github&utm_medium=referral&page=upgrade-pr

package.json

@@ -25,7 +25,7 @@
         "lodash.assign": "^4.2.0",
         "node-notifier": "^8.0.1",
         "path": "^0.12.7",
-        "postcss": "^8.4.25",
+        "postcss": "^8.4.26",
         "postcss-csso": "^5.0.1",
         "sass": "^1.63.6",
         "smooth-scroll": "^16.0.3",